Inputs for EPW¶
List of inputs of EPW v6.0¶
Structure of the input data¶
title line
&inputepw¶
A a2f, adapt_ethrdg_plrn, ahc_nbnd, ahc_nbndskip, ahc_win_max, ahc_win_min, amass, asr_typ, assume_metal, a_gap0
B band_plot, bands_skipped, bfieldx, bfieldy, bfieldz, bnd_cum, broyden_beta, broyden_ndim
C cal_psir_plrn, carrier, calc_nelec_wann, conv_thr_iaxis, conv_thr_plrn, conv_thr_racon, conv_thr_raxis, cumulant
D degaussq, degaussw, delta_approx, delta_qsmear, delta_smear, dvscf_dir, do_CHBB, do_tdbe, dt_tdbe, dph_tdbe
E efermi_read, eig_read, elecselfen, elecselfen_type, eliashberg, elph, emax_coulomb, emin_coulomb, ep_coupling, epbwrite, epbread, epexst, ephwrite, epmatkqread, eps_acoustic, epsiHEG, eps_cut_ir, epw_memdist, epwread, epwwrite, etf_mem, ethrdg_plrn, exciton, explrn, ef_c_tdbe, ef_v_tdbe, ephmat_dir
F fermi_diff, fermi_energy, fermi_plot, fila2f, fildvscf, filirobj, filkf, filnscf_coul, filqf, filukk, filukq, fixsym, fsthick
G gap_edge, gb_scattering, gb_only, gb_size, griddens, gridsamp
I imag_read, init_ethrdg_plrn, init_k0_plrn, init_ntau_plrn, init_plrn, init_sigma_plrn, interp_Ank_plrn, interp_Bqu_plrn, int_mob, io_lvl_plrn, iterative_bte, iverbosity, ii_g, ii_scattering, ii_only, ii_lscreen, ii_partion, ii_charge, ii_n, ii_eda, init_type_tdbe, init_sigma_tdbe
L lacon, laniso, lifc, limag, lindabs, liso, longrange, lopt_w2b, lpade, lphase, lpolar, lreal, ltrans_crta, lscreen, lunif, loptabs, len_mesh, lwfpt, lscreen_tdbe
M max_memlt, meff, mob_maxiter, mob_maxfreq, mob_nfreq, mp_mesh_k, mp_mesh_q, muc, muchem, meshnum
N nbndsub, ncarrier, nc, nel, nest_fn, nethrdg_plrn, ngaussw, niter_plrn, nk1, nk2, nk3, nkf1, nkf2, nqf3, nq1, nq2, nq3, nqf1, nqf2, nqf3, npade, nqsmear, nqstep, n_r, nsiter, nsmear, nstemp, nswi, nswc, nswfc, nw, nw_specfun, nq_init, nbndc_explrn, nbndv_explrn, negnv_explrn, nkf1d, nkf2d, nkf3d, nqf1d, nqf2d, nqf3d
O omegamax, omegamin, omegastep
P phonselfen, plselfen, plrn, positive_matsu, prefix, prtgkk, pwc, plot_explrn_e, plot_explrn_h, phph_tdbe, phwmin_tdbe
R rand_nq, rand_nk, rand_q, rand_k, restart, restart_filq, restart_plrn, restart_step, restart_tdbe
S scell_mat, scell_mat_plrn, scr_typ, scatread, scattering, scattering_serta, scattering_0rta, scissor, selecqread, smear_rpa, specfun_el, specfun_ph, specfun_pl, sr_crta, system_2d, shortrange, step_wf_grid_plrn, start_mesh, step_k1_explrn, step_k2_explrn, step_k3_explrn, solver_tdbe
T temps, tc_linear, tc_linear_solver, type_plrn, temp_el_tdbe, temp_ph_tdbe, twrite_tdbe, carr_dyn_tdbe
V vme
W wannierize, wepexst, wmax, wmax_specfun, wmin, wmin_specfun, wscut, wsfc
/
—- If wannierize = .true. the following input variable apply
auto_projections, dis_froz_min, dis_froz_max, iprint, num_iter, proj, reduce_unk, scdm_entanglement, scdm_mu, scdm_proj, scdm_sigma, wannier_plot, wannier_plot_list, wannier_plot_radius, wannier_plot_scale, wannier_plot_supercell, wdata
—- If a file named quadrupole.fmt is present in the running directory, the code will use quadrupoles to perform the interpolation of the electron-phonon matrix elements and dynamical matrices. The structure of the file is as follow:
atom dir Qxx Qyy Qzz Qyz Qxz Qxy
1 1 XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
1 2 XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
1 3 XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
2 1 XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
2 2 XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
2 3 XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
...
where XXXXXXXX have to be replaced by the value of the quadrupoles which can be obtained, for example, using the ABINIT software
a2f¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Calculate Eliashberg spectral function, \(\alpha^2F(\omega)\), transport Eliashberg spectral function \(\alpha^2 F_{\rm tr}(\omega)\), and phonon density of states \(F(\omega)\). Only allowed in the case of phonselfen = .true.
|
ahc_nbnd¶
Type |
INTEGER
|
Description |
Number of bands included in the electron self-energy calculation based on the Allen-Heine-Cardona theory. Must be the same as in the input file for the previous ph.x calculation with electron_phonon = ‘ahc’. Use only if lwfpt = .true.
|
ahc_nbndskip¶
Type |
INTEGER
|
Description |
Number of low-lying bands excluded in the electron self-energy calculation based on the Allen-Heine-Cardona theory. Must be the same as in the input file for the previous ph.x calculation with electron_phonon = ‘ahc’.
|
ahc_win_max¶
Type |
REAL
|
Description |
The energy upper bound of active-space window for the electron self-energy, expressed in eV. This energy must be below the dis_froz_max.
|
ahc_win_min¶
Type |
REAL
|
Description |
The energy lower bound of active-space window for the electron self-energy, expressed in eV. This energy must be above the dis_froz_min, dis_froz_max.
|
amass(:)¶
Variable |
amass(i), i=1,ntyp
|
Type |
REAL
|
Default |
0.0
|
Description |
Atomic mass [amu] of each atomic type. If not specified, masses are read from data file.
|
asr_typ¶
Type |
CHARACTER
|
Default |
‘simple’
|
Description |
Kind of acoustic sum rule that can be imposed in real space. Possible ASR are ‘simple’, ‘crystal’, ‘one-dim’ and ‘zero-dim’.
|
assume_metal¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Assume we have a metal. This flag should only be activated in the context of transport (conductivity or resistivity) calculations. In that case use a Fermi-Dirac distribution.
|
a_gap0¶
Type |
REAL
|
Default |
1.0d0
|
Description |
Set the shape of initial guess of gap function.
a_gap0 = negative, use a step function.
a_gap0 = 0.0, use an initial guess with no frequency dependence.
a_gap0 > 10^-8, use the Lorentzian: f(iw) = gap0 / (1 + a_gap0 * (iw / wsphmax)**2).
|
band_plot¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
bands_skipped¶
Type |
CHARACTER
|
Default |
'' |
Description |
List of bands to exclude from the wannierization, where the number of excluded bands should be smaller or equal to nbndskip. For example,
bands_skipped = 'exclude_bands = 1:5' means the first 5 bands are excluded from the wannierization. |
bfieldx, bfieldy, bfieldz¶
Type |
REAL
|
Default |
0.0
|
Description |
The magnetic field in the x, y and z Cartesian directions in [Tesla].
|
bnd_cum¶
Type |
INTEGER
|
Default |
1
|
Description |
Band index for which the cumulant calculation is done. For more than one band, you need to perform multiple calculation and add the results together.
|
broyden_beta¶
Type |
REAL
|
Default |
0.7
|
Description |
Mixing factor for Broyden mixing scheme.
|
broyden_ndim¶
Type |
INTEGER
|
Default |
8
|
Description |
Number of iterations used in the Broyden mixing scheme.
|
carrier¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. it computes the intrinsic electron or hole mobility such that the carrier concentration is given by ncarrier.
|
calc_nelec_wann¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. it computes number of electrons in the wannierized band structure.
|
conv_thr_iaxis¶
Type |
REAL
|
Default |
1.d-05
|
Description |
Convergence threshold for iterative solution of imaginary-axis Eliashberg equations.
|
conv_thr_racon¶
Type |
REAL
|
Default |
5.d-05
|
Description |
Convergence threshold for iterative solution of the analytic continuation of Eliashberg equations from imaginary- to real-axis.
|
conv_thr_raxis¶
Type |
REAL
|
Default |
5.d-04
|
Description |
Convergence threshold for iterative solution of real-axis Eliashberg equations.
|
cumulant¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. calculates the electron spectral function using the cumulant expansion method. Can be used as independent postprocessing by setting ep_coupling =.false.
|
degaussq¶
Type |
REAL
|
Default |
0.05
|
Description |
Smearing for sum over q in the e-ph coupling in [meV]
|
degaussw¶
Type |
REAL
|
Default |
0.025
|
Description |
Smearing in the energy-conserving delta functions in [eV]
|
delta_approx¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. the double delta approximation is used to compute the phonon self-energy.
|
delta_qsmear¶
Type |
REAL
|
Default |
0.05
|
Description |
Change in the energy for each additional smearing in the a2f in [meV].
|
delta_smear¶
Type |
REAL
|
Default |
0.01
|
Description |
Change in the energy for each additional smearing in the phonon self-energy in [eV]
|
dvscf_dir¶
Type |
CHARACTER
|
Default |
‘./’
|
Description |
Directory where ‘prefix.[dvscf|dyn]_q??’ files are located.
|
do_CHBB¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Use CHBB theory for optical absorption calculation.
|
efermi_read¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. the Fermi energy is read from the input file.
|
eig_read¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. then read a set of eigenvalues from ksdata.fmt. Can be used to read GW (or other) eigenenergies. The code expect a file called “prefix.eig” to be read. One need to provide the same number of bands as in the nscf calculations and all k-points.
|
elecselfen¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Calculate the electron self-energy from the el-ph interaction
|
elecselfen_type¶
Type |
CHARACTER
|
Default |
‘nonadiabatic’
|
Description |
If ‘nonadiabatic’, compute the non-adiabatic electron self-energy (default). If ‘adiabatic’, compute the adiabatic electron self-energy. Only to be used in non-IR-active materials. See J. Chem. Phys. 143, 102813 (2015) for more information.
|
eliashberg¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. solve the Eliashberg equations and/or calculate the Eliashberg spectral function.
1) if laniso =.true., the anisotropic Eliashberg equations are solved. This requires that .ephmat, .freq, .egnv, .ikmap files are read from the disk. The files are written when ephwrite =.true. in the input file (see ephwrite variable).
2) if liso =.true., the isotropic Eliashberg equations are solved. This requires that either (a) .ephmat, .freq, .egnv, .ikmap files (see ephwrite variable) or (b) isotropic Eliashberg spectral function file (see fila2f variable) are read from the disk.
3) if .not. laniso and .not. liso , the Eliashberg spectral function is calculated. This requires that .ephmat, .freq, .egnv, .ikmap files are read from the disk. The files are written when ephwrite =.true. in the input file (see ephwrite variable).
Note: To reuse .ephmat, .freq, .egnv, .ikmap files obtained in a previous run, one needs to set ep_coupling =.false., elph =.false., and ephwrite =.false. in the input file.
|
elph¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. calculate e-ph coefficients.
|
emax_coulomb¶
Type |
REAL
|
Default |
1.0d5
|
Description |
Upper bound of outer window. Only the bands lower than “emax_coulomb + efermi” are considered when icoulomb >= 1.
|
emin_coulomb¶
Type |
REAL
|
Default |
-1.0d5
|
Description |
Lower bound of outer window. Only the bands upper than “emin_coulomb + efermi” are considered when icoulomb >= 1.
|
ep_coupling¶
Type |
LOGICAL
|
Default |
.true.
|
Description |
If .true. run e-ph coupling calculation.
|
epbwrite, epbread¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If epbwrite = .true., the electron-phonon matrix elements in the coarse Bloch representation and relevant data (dyn matrices) are written to disk. If epbread = .true. the above quantities are read from the ‘prefix.epb’ files. Pool dependent files.
|
epexst¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. then prefix.epmatwp files are already on disk (don’t recalculate). This is a debugging parameter.
|
ephwrite¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Writes 4 files (in prefix.ephmat directory) that are required when solving the Eliashberg equations. ‘ephmatXX’ (XX: pool dependent files) files with e-ph matrix elements within the Fermi window (fsthick) on fine k and q meshes on the disk, ‘freq’ file contains the phonon frequencies, ‘egnv’ file contains the eigenvalues within the Fermi window, and ‘ikmap’ file contains the index of the k-point on the irreducible grid within the Fermi window. These files are required to solve the Eliashberg equations when eliashberg = .true.. The files can be reused for subsequent evaluations of the Eliashberg equations at different temperatures. ephwrite doesn’t work with random k- or q-meshes and requires nkf1,nkf2,nkf3 to be multiple of nqf1,nqf2,nqf3.
|
epmatkqread¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. restart an IBTE calculation from scattering written to files.
|
eps_acoustic¶
Type |
REAL
|
Default |
0.1.d0
|
Description |
The lower boundary for the phonon frequency in el-ph and a2f calculations in [cm-1].
|
epsiHEG¶
Type |
REAL
|
Default |
0.25d0
|
Description |
Dielectric constant at zero doping for electron-plasmon.
|
eps_cut_ir¶
Type |
REAL
|
Default |
1.0d-5
|
Description |
A threshold to ignore negligibly small IR coefficients. Works only with gridsamp = 2.
|
epw_memdist¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Distribute electron-phonon coupling array among MPI processes, reducing memory usage in the interpolation step. Works only with etf_mem == 0.
|
epwread¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If epwread = .true., the electron-phonon matrix elements in the coarse Wannier representation are read from the ‘epwdata.fmt’ and ‘XX.epmatwpX’ files. Each pool reads the same file. It is used for a restart calculation and requires kmaps = .true. A prior calculation with epwwrite = .true is also required.
|
epwwrite¶
Type |
LOGICAL
|
Default |
.true.
|
Description |
If epwwrite = .true., the electron-phonon matrix elements in the coarse Wannier representation and relevant data (dyn matrices) are written to disk. Each pool reads the same file.
|
etf_mem¶
Type |
INTEGER
|
Default |
1
|
Description |
If etf_mem = 1, then all the fine Bloch-space el-ph matrix elements are stored in memory (faster). When etf_mem = 1, more IO (slower) but less memory is required. When etf_mem = 2, an additional loop is done on mode for the fine grid interpolation part. This reduces the memory further by a factor “nmodes”. The etf_mem = 3 is like etf_mem = 1 but the fine k-point grid is generated with points within the fsthick window using k-point symmetry (mp_mesh_k = .true. is needed) and the fine q-grid is generated on the fly. The option etf_mem = 3 is used for transport calculations with ultra dense fine momentum grids.
|
exciton¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Calculate exciton-phonon coupling and optical transition.
|
explrn¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. activates the calculation of excitonic polaron. Only relevant when epwread = .true.
|
fbw¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. solve the anisotropic FBW Migdal-Eliashberg equations.
|
fermi_diff¶
Type |
REAL
|
Default |
1.d0
|
Description |
Difference between Fermi energy and band edge (in eV). Only relevant when lscreen = .true.
|
fermi_energy¶
Type |
REAL
|
Default |
0.d0
|
Description |
Value of the Fermi energy read from the input file in [eV].
|
fermi_plot¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true., write Fermi surface files (in .cube format which can be plotted with VESTA) on nkf1, nkf2, nqf3.
|
fila2f¶
Type |
CHARACTER
|
Default |
'' |
Description |
Input file with isotropic Eliashberg spectral function. The file contains the Eliashberg spectral function as a function of frequency in [meV]. This file can only be used to calculate the isotropic Eliashberg equations. In this case
*.ephmat, *.freq, *.egnv, and *.ikmap files are not required. |
fildvscf¶
Type |
CHARACTER
|
Default |
'' |
Description |
Output file containing deltavscf (not used in calculation)
|
filirobj¶
Type |
CHARACTER
|
Default |
'' |
Description |
Input file with the objects of IR-basis. The file contains the IR basis functions and the corresponding sampling points.
See also EPW/irobjs/README.md located under the installation directory.
|
filkf¶
Type |
CHARACTER
|
Default |
‘./’
|
Description |
File which contains the fine k-mesh or the k-path of electronic states to be calculated for elinterp. Crystal coordinates.
|
filnscf_coul¶
Type |
CHARACTER
|
Default |
'' |
Description |
filqf¶
Type |
CHARACTER
|
Default |
‘./’
|
Description |
File which contains the fine q-mesh or the q-path of phonon states to be calculated for phinterp. Crystal coordinates.
|
filukk¶
Type |
CHARACTER
|
Default |
‘prefix.ukk’
|
Description |
The name of the file containing the rotation matrix U(k) which describes the MLWFs.
|
filukq¶
Type |
CHARACTER
|
Default |
‘prefix.ukq’
|
Description |
The name of the file containing the rotation matrix U(k+q) which describes the MLWFs.
|
fixsym¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. try to fix the symmetry-related issues.
|
fsthick¶
Type |
REAL
|
Default |
1.d10
|
Description |
Width of the Fermi surface window to take into account states in the self-energy delta functions in [eV]. Narrowing this value reduces the number of bands included in the selfenergy calculations.
|
gap_edge¶
Type |
REAL
|
Default |
0.d0
|
Description |
Initial guess for the superconducting gap edge if gap_edge .gt. 0.d0 in [eV]. Otherwise the initial guess for the gap is estimated based on the critical temperature found from the Allen-Dynes formula and BCS ratio (2*gap/T_c=3.52)
|
gb_scattering¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .TRUE. it calculates grain boundary scattering rate \(\tau_{n\bf{k}} = | \bf{v}_{n\bf{k}} | / L\),
where \(\bf{v}_{n\bf{k}}\) is band group velocity and \(L\) is grain size
|
gb_only¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .TRUE. it calculates only the grain-boundary-limitted mobility
|
gb_size¶
Type |
REAL
|
Default |
0.0d0
|
Description |
Grain size \(L\) in unit of nm
|
griddens¶
Type |
REAL
|
Default |
1.0d0
|
Description |
Measure of sparsity of the grid (larger values give denser mesh). Works only with gridsamp = 1.
|
gridsamp¶
Type |
INTEGER
|
Default |
0
|
Description |
Type of the Matsubara freq. sampling
gridsamp = -1 reads Matsubara frequencies from a file named matsu-freq.in
gridsamp = 0 generates uniform Matsubara frequency grid
gridsamp = 1 generates sparse Matsubara frequency grid
gridsamp = 2 read from file sparse-ir Matsubara frequencies from a file specified by filirobj
gridsamp = 3 generates uniform Matsubara frequency grid for FFT
If gridsamp = 2, the IR object file must be specified by filirobj. You can download some IR object files below.
See also EPW/irobjs/README.md located under the installation directory.
|
icoulomb¶
Type |
INTEGER
|
Default |
0
|
Description |
Specify the method for calculating the Coulomb contribution to the Eliashberg eqs. This flag only works when fbw = .true. and gridsamp = 2.
icoulomb = 0, consider only the contribution from the states within fsthick window
icoulomb = 1, consider the contribution from the states within and outside fsthick window
|
imag_read¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. read from file the superdconducting gap and renormalization function on the imaginary-axis at a temperature XX. The required file is ‘prefix.imag_aniso_XX’. The temperature should be specified as temps(1) =XX in the input file. This flag works if limag =.true. and laniso =.true., and can be used to:
(1) solve the Eliashberg equations on the real-axis with lpade =.true. or lacon =.true. starting from the imaginary-axis solutions at temperature XX;
(2) solve the Eliashberg equations on the imaginary-axis at temperatures grater than XX using as a starting point the gap estimated at temperature XX.
(3) write to file the superconducting gap on the Fermi surface in cube format at temperature XX. The output file is ‘prefix.imag_aniso_gap_XX_YY.cube’, where YY is the band number within the chosen energy window during the EPW calculation. The file is written if iverbosity =2.
|
int_mob¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. and carrier = .false. it compute the intrinsic mobility such that the electron carrier concentration and hole concentration are the same (only one Fermi level) and give both electron and hole mobility in the same run. If the gap is too big, the number of carrier will be so small that the code will be unstable. If .true. and carrier = .true. it will compute the intrinsic electron and hole mobility with two Fermi level such that the electron and hole carrier concentration is ncarrier.
|
iterative_bte¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. it compute the iterative Boltzmann Transport Equation (IBTE) intrinsic mobility such that the electron carrier concentration and hole concentration are the same (only one Fermi level) and give both electron and hole mobility in the same run. If the gap is too big, the number of carrier will be so small that the code will be unstable. If .true. and carrier = .true. it will compute the intrinsic electron and hole mobility with two Fermi level such that the electron and hole carrier concentration is ncarrier. Also see mob_maxiter.
Note that the IBTE can only be solved on a homogeneous grid. You can use k-point symmetry to reduce the computational time with mp_mesh_k.
|
iverbosity¶
Type |
INTEGER
|
Default |
0
|
Description |
0 = short output
1 = verbose output.
2 = verbose output for the superconducting part only.
3 = verbose output for the electron-phonon part only [mode resolved linewidths etc..].
|
ii_g¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. it calculates the ionized impurity matrix elements
|
ii_scattering¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. it calculates the the carrier-ionized impurity scattering rate
|
ii_only¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. it calculates only the ionized-impurity-limitted mobility
|
ii_lscreen¶
Type |
LOGICAL
|
Default |
.true.
|
Description |
If .true. it calculates and uses free-carrier screening of ii_g matrix elements, else calculations will
diverge with increasing density of k-point due to 1/(q^4) divergence for ionized impurity scattering rate
|
ii_partion¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. it accounts for partial ionization
|
ii_charge¶
Type |
REAL
|
Default |
1.0
|
Description |
Charge of the ionized impurities in units of elementary charge
|
ii_n¶
Type |
REAL
|
Default |
0.0d0
|
Description |
Density of impurities, input in units of cm^-3 (cm^-2 in 2D-currently under development)
|
ii_eda¶
Type |
REAL
|
Default |
0.0d0
|
Description |
Ionization energy of the donor or accpetor impurity, for partial ionization calculations
|
kerread¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. read Kp and Km kernels from files .ker when solving the real-axis Eliashberg equations.
|
kerwrite¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. write Kp and Km kernels to files .ker when solving the real-axis Eliashberg equations.
|
kmaps¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Generate the map k+q –> k for folding the rotation matrix U(k+q). If .true., the program reads ‘prefix.kmap’ and ‘prefix.kgmap’ from file. If .false., they are calculated.
Note that for a restart with epwread =.true., kmaps also needs to be set to true (since the information to potentially calculate kgmaps is not generated in a restart run). However, the files “prefix.kmap” and “prefix.kgmap” themselves are actually not used if epwread=.true. and hence need not actually be there.
|
lacon¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
laniso¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. solve the anisotropic Eliashberg equations on the imaginary-axis. To solve the equations,
*.ephmat, *.freq, *.egnv, and *.ikmap files should be provided. These files are described under ephwrite variable. |
lifc¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. uses the real-space inter-atomic force constant generated by q2r.x. The resulting file must be named “ifc.q2r”. The file has to be placed in the same directory as the dvscf files. In the case of SOC, the file must be named “ifc.q2r.xml” and be in xml format. See asr_typ for the type of acoustic sum rules that can be imposed.
|
limag¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. solve the imaginary-axis Eliashberg equations.
|
lindabs¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
liso¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. solve the isotropic Eliashberg equations on the real- or imaginary-axis. To solve the equations provide either: (1) Eliashberg spectral function file using fila2f variable. (2)
*.ephmat, *.freq, *.egnv, and *.ikmap files. These files are described under ephwrite variable. |
lpade¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. Padé approximants to continue the imaginary-axis Eliashberg equations to real-axis. This works with limag =.true.
|
lphase¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. then fix the gauge for the interpolated dynamical matrix and electronic Hamiltonian.
|
lpolar¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. enable the correct Wannier interpolation in the case of polar material.
|
lreal¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. solve the Eliashberg equations directly on the real-axis. Only the isotropic case (liso =.true.) is implemented.
|
ltrans_crta¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. it calculates the transport properties with constant relaxation time approximation (CRTA). The scattering rate should be given by sr_crta.
|
lscreen¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. the el-ph matrix elements are screened by the RPA or TF dielectric function. See (scr_typ).
|
lunif¶
Type |
LOGICAL
|
Default |
.true.
|
Description |
If .true. a uniform frequency grid is defined between (wsfc,wscut) for solving the real-axis Eliashberg equations. Works only with lreal =.true.
|
lwfpt¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. enable Wannier function perturbation theory calculations. See Phys. Rev. X 11, 041053 (2021) for more information.
|
longrange¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. only the long-range part of the electron-phonon matrix elements are calculated. Works only with lpolar =.true.
|
lopt_w2b¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. use optimized version of Wannier-to-Bloch Fourier transformation for the electron-phonon coupling (see Eqs. 8 and 9 of SciPost Phys. 15, 062 (2023)). To be used only when the q points are sampled from a uniform mesh or a product of one-dimensional meshes.
|
loptabs¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. optical absorption spectra including phonon-assisted and direct transitions using quasi-degenerate perturbation theory.
|
len_mesh¶
Type |
INTEGER
|
Default |
1
|
Description |
Number of quasi-degenerate meshgrids for optical absorption spectra using quasi-degenerate perturbation theory.
|
max_memlt¶
Type |
REAL
|
Default |
2.85d0
|
Description |
Maximum memory that can be allocated per pool in [Gb].
|
meff¶
Type |
REAL
|
Default |
12.0
|
Description |
Density of state effective mass for electron-plasmon.
|
mob_maxfreq¶
Type |
REAL
|
Default |
100
|
Description |
Maximum frequency (in [meV]) for spectral decomposition of scattering rates. Typically that freq. is the highest phonon freq. Only works with iverbosity == 3.
|
mob_nfreq¶
Type |
INTEGER
|
Default |
100
|
Description |
Number of frequency steps from 0 to mob_maxfreq used for the spectral decomposition of the scattering rates. Only works with iverbosity == 3.
|
mob_maxiter¶
Type |
INTEGER
|
Default |
50
|
Description |
Maximum number of iteration during the IBTE.
|
mp_mesh_k¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true., fine electronic mesh is in the irr. wedge, else a uniform grid throughout the BZ is used.
|
mp_mesh_q¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true., fine phonon mesh is in the irr. wedge, else a uniform grid throughout the BZ is used. Not currently in use.
|
meshnum¶
Type |
INTEGER
|
Default |
1
|
Description |
Final meshgrid to be performed using quasi-degenerate perturbation theory, maximum value:ref:len_mesh - 1, used with start_mesh for restart calculations.
|
nbndsub¶
Type |
INTEGER
|
Default |
0
|
Description |
Number of wannier functions to utilize.
|
nbndc_explrn¶
Type |
INTEGER
|
Default |
2
|
Description |
Number of conduction bands for exciton calculation.
|
nbndv_explrn¶
Type |
INTEGER
|
Default |
2
|
Description |
Number of valence bands for exciton calculation.
|
negnv_explrn¶
Type |
INTEGER
|
Default |
1
|
Description |
Number of exciton states to be included in the ex-polaron calculation.
|
ncarrier¶
Type |
REAL
|
Default |
1.0d+13
|
Description |
If carrier = .true. then compute the intrinsic mobility with ncarrier concentration (in cm^-3). If ncarrier is positive it will compute the electron mobility and if it is negative it will compute the hole mobility. If int_mob is also .true. then it will compute both the electron and hole mobility, which is the recommended way to compute mobility.
|
nc¶
Type |
REAL
|
Default |
4.0d0
|
Description |
Number of carriers per unit cell that participate to the conduction in the Ziman’s resistivity formula. Typically this corresponds to the number of bands crossing the Fermi level. This can be a fractional number.
|
nel¶
Type |
REAL
|
Default |
0.01
|
Description |
Carrier concentration for electron-plasmon.
|
nest_fn¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Calculate the electronic nesting function.
|
ngaussw¶
Type |
INTEGER
|
Default |
1
|
Description |
Smearing type for FS average after Wannier interpolation
|
nk1, nk2, nk3¶
Type |
INTEGER
|
Default |
0
|
Description |
Dimensions of the coarse electronic grid, corresponds to the nscf calculation and wfs in the outdir.
|
nkf1, nkf2, nqf3¶
Type |
INTEGER
|
Default |
0
|
Description |
Dimensions of the fine electron grid, if filkf is not given.
|
nq1, nq2, nq3¶
Type |
INTEGER
|
Default |
0
|
Description |
Dimensions of the coarse phonon grid, corresponds to the nqs list.
|
nqf1, nqf2, nqf3¶
Type |
INTEGER
|
Default |
0
|
Description |
Dimensions of the fine phonon grid, if filqf is not given.
|
npade¶
Type |
INTEGER
|
Default |
90
|
Description |
Percentage of Matsubara points used in Padé continuation.
|
nqsmear¶
Type |
INTEGER
|
Default |
10
|
Description |
Number of different smearings used to calculate the a2f.
|
nqstep¶
Type |
REAL
|
Default |
500
|
Description |
Number of steps used to calculate the a2f
|
n_r¶
Type |
REAL
|
Default |
1.0
|
Description |
Refractive index used when lindabs = .true.
|
nsiter¶
Type |
INTEGER
|
Default |
40
|
Description |
Number of iteration for the self-consistency cycle when solving the real- or imaginary-axis Eliashberg equations.
|
nsmear¶
Type |
INTEGER
|
Default |
1
|
Description |
Number of different smearings used to calculate the phonon self-energy.
|
nstemp¶
Type |
INTEGER
|
Default |
1
|
Description |
Number of temperature points used for superconductivitiy, transport, indabs, etc.. If nstemp is left blank, or is equivalent to the number of entries in temps(:), then the temperatures provided in temps(:) are used. If nstemp>2 and only two temperatures are given in temps(:), then an evenly spaced temperature grid with steps between points given by (temps(2) - temps(1)) / (nstemp-1) is generated. This grid contains nstemp points. nstemp cannot be larger than 50.
|
nswi¶
Type |
INTEGER
|
Default |
0
|
Description |
nswc¶
Type |
INTEGER
|
Default |
0
|
Description |
nswfc¶
Type |
INTEGER
|
Default |
0
|
Description |
nq_init¶
Type |
INTEGER
|
Default |
-1
|
Description |
Phonon occupation for quasi-degenerate perturbation theory, -1 for Bose-Einstein, -2 for integer Bose-Einstein, -3 for Monte-Carlo method of integration.
|
muc¶
Type |
REAL
|
Default |
0.d0
|
Description |
Effective Coulomb potential used in the Eliashberg equations.
|
muchem¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. solve the FBW Migdal-Eliashberg equations with variable chemical potential. Works only with fbw = .true.
|
nw¶
Type |
INTEGER
|
Default |
10
|
Description |
Number of bins for frequency scan in delta( e_k - e_k+q - w).
|
nw_specfun¶
Type |
INTEGER
|
Default |
100
|
Description |
Number of bins for frequency in electron spectral function.
|
omegamax¶
Type |
REAL
|
Default |
10
|
Description |
Photon energy maximum (in eV) when lindabs = .true.
|
omegamin¶
Type |
REAL
|
Default |
0
|
Description |
Photon energy minimum (in eV) when lindabs = .true.
|
omegastep¶
Type |
REAL
|
Default |
1
|
Description |
Steps in photon energy (in eV) when lindabs = .true.
|
outdir¶
Type |
CHARACTER
|
Default |
‘./’
|
Description |
Scratch directory.
|
phonselfen¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Calculate the phonon self-energy from the el-ph interaction.
|
plot_explrn_e¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. plot the electron density of excitonic polaron. Will skip the explrn calculations
|
plot_explrn_h¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. plot the hole density of excitonic polaron. Will skip the explrn calculations
|
plselfen¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
positive_matsu¶
Type |
LOGICAL
|
Default |
.true.
|
Description |
If .true. the domain of Matsubara frequency is limited to positive.
|
prefix¶
Type |
CHARACTER
|
Default |
‘pwscf’
|
Description |
Prepended to input/output filenames. Must be the same used in the calculation of the wfs and phonons.
|
prtgkk¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Allows to print the electron-phonon vertex |g| (in meV) for each q-point, k-point, i-band, j-band and modes.
Note: Average over degenerate i-band, j-band and modes is performed but not on degenerate k or q-points.
Warning: this produces huge text data in the main output file and considerably slows down the calculation.
Suggestion: Use only 1 k-point (like Gamma).
|
pwc¶
Type |
REAL
|
Default |
1.0
|
Description |
QD_bin¶
Type |
REAL
|
Default |
0.1
|
Description |
Size of many-body meshgrid for quasi-degenerate perturbation theory (in eV).
|
QD_min¶
Type |
REAL
|
Default |
0.0
|
Description |
Starting energy for quasi-degenerate perturbation theory (in eV).
|
rand_nq, rand_nk¶
Type |
INTEGER
|
Default |
1
|
Description |
number of random q,k-vectors on the fine mesh
|
rand_q, rand_k¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
q/k-vectors on the fine mesh are generated randomly
|
restart¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Create a restart point every restart_step q-points from the fine grid during the interpolation stage.
|
restart_filq¶
Type |
CHARACTER
|
Default |
'' |
Description |
Input file to restart from an exisiting q-file. Use to merge different q-grid scattering rates.
|
restart_step¶
Type |
INTEGER
|
Default |
100
|
Description |
Frequency of restart points during the fine q-grid interpolation phase. This produces restart files called XXX.sigma_restart1
|
scr_typ¶
Type |
INTEGER
|
Default |
0
|
Description |
If 0 calculates the Lindhard screening, if 1 the Thomas-Fermi screening. Only relevant if lscreen = .true.
|
scatread¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. the current scattering rate file is read from file.
|
scattering¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. computes scattering rates. See also scattering_serta for the type of scattering.
|
scattering_serta¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. computes scattering rates in the self-energy relaxation time approximation. See S. Poncé, E. R. Margine and F. Giustino, Phys. Rev. B 97, 121201 (2018) for more information.
|
scattering_0rta¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. then the scattering rates are calculated using 0th order relaxation time approximation.
|
scissor¶
Type |
REAL
|
Default |
0.0
|
Description |
Gives the value of the scissor shift of the gap (in eV).
|
selecqread¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. then restart from the selecq.fmt file
|
smear_rpa¶
Type |
REAL
|
Default |
0.05d0
|
Description |
Smearing for the calculation of the Lindhard function (in eV). Only relevant if lscreen = .true.
|
specfun_el¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Calculate the electron spectral function from the e-ph interaction. The relevant variables in this case are wmin_specfun, wmax_specfun and nw_specfun.
|
specfun_ph¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Calculate the phonon spectral function from the e-ph interaction. The relevant variables in this case are wmin_specfun, wmax_specfun and nw_specfun.
|
specfun_pl¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Calculate electron-plasmon spectral function. The relevant variables in this case are wmin_specfun, wmax_specfun and nw_specfun. See also nel, meff, epsiHEG.
|
sr_crta¶
Type |
REAL
|
Default |
1.0d0
|
Description |
If ltrans_crta = .true. then compute the transport properties with constant relaxation time approximation with a constant scattering rate sr_crta in [THz].
|
system_2d¶
Type |
CHARACTER
|
Default |
‘no’
|
Description |
‘no’ then 3D bulk materials
‘gaussian’ then the long-range terms include dipoles only and the range separation function is approximated by a Gaussian following Ref. Phys. Rev. B 94, 085415 (2016)
‘dipole_sp’ then the long-range terms include dipoles following PRB 107, 155424 (2023)
‘quadrupole’ then the long-range terms include dipoles and quadrupoles terms following PRL 130, 166301 (2023) and requires the presence of a “quadrupole.fmt” file.
‘dipole_sh’ then the long-range terms include dipoles following [PRB 105, 115414 (2022)]
|
shortrange¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. then computes the short-range part of the electron-phonon matrix elements. Works only with lpolar =.true.
|
start_mesh¶
Type |
INTEGER
|
Default |
1
|
Description |
Starting mesh for optical absorption for quasi-degenerate perturbation theory, used with meshnum for restart calculations.
|
step_k1_explrn¶
Type |
INTEGER
|
Default |
1
|
Description |
In the full k-grid, choose k points for every step_k_explrn to construct the exciton polaron Hamiltonian. For example, if the full grid is 6x6x6, and step_k1_explrn = step_k2_explrn = step_k3_explrn = 2, then a 3x3x3 grid will be used in the end. Note when constructing the exciton-phonon coupling matrix, the full grid is always used.
|
step_k2_explrn¶
Type |
INTEGER
|
Default |
1
|
Description |
Check the description of step_k1_explrn
|
step_k3_explrn¶
Type |
INTEGER
|
Default |
1
|
Description |
Check the description of step_k1_explrn
|
temps¶
Type |
REAL(nstemp)
|
Default |
300.d0 Kelvin
|
Description |
Temperature values used in superconductivitiy, transport, indabs, etc. in kelvin unit. If no temps are provided, temps=300 and nstemp =1. If two temps are provided, with temps(1)<temps(2) and nstemp >2, then temps is transformed into an evenly spaced grid with nstemp points, including temps(1) and temps(2) as the minimum and maximum values, respectively [Ex)
nstemp = 5 temps = 300 500]. In this case, points are spaced according to (temps(2) - temps(1)) / (nstemp-1). Otherwise, temps is treated as a list, with the given temperatures used directly [Ex) temps = 17 20 30]. No more than 50 temperatures can be supplied in this way. |
tc_linear¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. linearized Eliashberg eqn. for superconducting transition temperature Tc will be solved.
|
tc_linear_solver¶
Type |
CHARACTER
|
Default |
‘power’
|
Description |
Algorithm to solve Tc eigenvalue problem. Possible algorithms are ‘power’, and ‘lapack’.
|
vme¶
Type |
CHARACTER
|
Default |
‘wannier’
|
Description |
if ‘dipole’ then computes the velocity as dipole+commutator = <psi_{mk} |p+i[V_{NL},r]| psi_{nk}>`. If ‘wannier’ then computes the velocity as dH_nmk/dk - i(e_nk-e_mk)A_nmk where A is the Berry connection. Note: Before v5.4, vme = .FALSE. was the velocity in the local approximation as <psi_mk|p|psi_nk>. Before v5.4, vme = .TRUE. was the same as ‘wannier’.
|
wannierize¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
Calculate the Wannier functions using W90 library calls and write rotation matrix to file ‘filukk’. If .false., filukk is read from disk.
|
wepexst¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. then prefix.epmatwe files are already on disk (don’t recalculate). This is a debugging parameter.
|
wmax¶
Type |
REAL
|
Default |
0.3d0
|
Description |
Max frequency in \(\delta( \epsilon_{\bf k} - \epsilon_{\bf{k}+\bf{q}} - \omega)\).
|
wmax_specfun¶
Type |
REAL
|
Default |
0.d0
|
Description |
The upper boundary for the frequency in the electron spectral function in [eV].
|
wmin¶
Type |
REAL
|
Default |
0.d0
|
Description |
Min frequency in \(\delta( \epsilon_{\bf k} - \epsilon_{\bf{k}+\bf{q}} - \omega)\).
|
wmin_specfun¶
Type |
REAL
|
Default |
0.d0
|
Description |
The lower boundary for the frequency in the electron spectral function in [eV].
|
wscut¶
Type |
REAL
|
Default |
1.d0
|
Description |
Upper limit over frequency integration/summation in the Eliashberg equations in [eV]. For limag =.true., wscut is ignored if the number of frequency points is given using variable nswi.
|
wsfc¶
Type |
REAL
|
Default |
0.5 * wscut
|
Description |
auto_projections¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. then automatically generate initial projections for Wannier90. It requires scdm_proj =.true.
|
dis_froz_min, dis_froz_max¶
Type |
REAL
|
Default |
-9999.d0, 9999.d0
|
Description |
Window which includes frozen states for Wannier90. See wannier90 documentation.
|
dis_win_min, dis_win_max¶
Type |
REAL
|
Default |
-9999.d0, 9999.d0
|
Description |
Minimum and maximum value of the outer window. See wannier90 documentation.
|
iprint¶
Type |
INTEGER
|
Default |
2
|
Description |
Verbosity level of Wannier90 code. See wannier90 documentation.
|
num_iter¶
Type |
INTEGER
|
Default |
200
|
Description |
Number of iterations passed to Wannier90 for minimization. See wannier90 documentation.
|
proj(:)¶
Type |
CHARACTER
|
Default |
'' |
Description |
Initial projections used in the Wannier90 calculation. Simple solution is
proj(1) = 'random'. See wannier90 documentation. |
reduce_unk¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. then plot Wannier functions on reduced grids.
|
scdm_entanglement¶
Type |
CHARACTER
|
Default |
‘isolated’
|
Description |
Disentanglement type in the SCDM algorithm.
|
scdm_mu¶
Type |
REAL
|
Default |
0.d0
|
Description |
Parameter for Wannier functions via SCDM algorithm.
|
scdm_proj¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. then calculate MLWFs without an initial guess via the SCDM algorithm.
|
scdm_sigma¶
Type |
REAL
|
Default |
1.d0
|
Description |
Parameter for Wannier functions via SCDM algorithm.
|
wannier_plot¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. then plot Wannier functions.
|
wannier_plot_list¶
Type |
CHARACTER
|
Default |
'' |
Description |
Field read for parsing Wannier function list.
|
wannier_plot_radius¶
Type |
REAL
|
Default |
3.5d0
|
Description |
Cut-off radius for plotting Wannier functions.
|
wannier_plot_scale¶
Type |
REAL
|
Default |
1.0d0
|
Description |
Scaling parameter for cube files.
|
wannier_plot_supercell¶
Type |
INTEGER(3)
|
Default |
(/5,5,5/)
|
Description |
Size of supercell for plotting Wannier functions
|
wdata(:)¶
Type |
CHARACTER
|
Default |
'' |
Description |
Any extra inforumation to be used in the Wannier90 calculation should be included here. These characters will be written to the ‘prefix.win’ file. For example to plot the first Wannier function in xcrysden format:
—————————————————–
wdata(1) = 'wannier_plot = true'wdata(2) = 'wannier_plot_list : 1'—————————————————–
See wannier90 documentation.
|
plrn¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. polaron calculations are activated.
|
type_plrn¶
Type |
INTEGER
|
Default |
-1
|
Description |
Polaron type, -1 for electron polaron and 1 for hole polaron.
|
init_plrn¶
Type |
INTEGER
|
Default |
1
|
Description |
Method to initialize the polaron wavefunction in the self-consistent loop. 1 for Gaussian wave function initialization (see init_sigma_plrn). 6 for fixed atomic displacement configuration \(\{\Delta \tau_{\kappa\alpha p}\}\) initialization (see init_ntau_plrn).
|
init_sigma_plrn¶
Type |
REAL
|
Default |
4.6
|
Description |
Width (in bohr) of Gaussian initialization wave function, \(A_{n\mathbf{k}} = \exp(-\sigma_p|\mathbf{k}-\mathbf{k}_0|)\), where \(\mathbf{k}_0\) is given by init_k0_plrn.
|
init_k0_plrn¶
Type |
REAL, DIMENSION(3)
|
Default |
\(\mathbf{k}_{\mathrm{CBM/VBM}}\)
|
Description |
\(\mathbf{k}\)-point (in crystal coordinates) in which the initialization Gaussian wave packet is centered.
|
init_ntau_plrn¶
Type |
INTEGER
|
Default |
1
|
Description |
Number of atomic displacements configurations to be considered if init_plrn =6. If init_ntau_plrn=1, the displacements are read from the dtau_disp.plrn file. If init_ntau_plrn=N>1, the displacements are read from the dtau_disp.plrn_i, where i=1, …, N, files.
|
conv_thr_plrn¶
Type |
REAL
|
Default |
1.0d-5
|
Description |
The converge threshold in the ab initio polaron equations (in bohr). The self-consistency is achieved when \(\max|\Delta \tau^{\mathrm{save}}_{\kappa\alpha p} - \Delta \tau_{\kappa\alpha p}| < \varepsilon_\mathrm{scf}\).
|
niter_plrn¶
Type |
INTEGER
|
Default |
50
|
Description |
The maximum number of iterations in the self-consistent loop in the ab initio polaron equations.
|
ethrdg_plrn¶
Type |
REAL
|
Default |
1.0d-6
|
Description |
Converge threshold (in Ry) in the diagonalization of the effective polaron Hamiltonian.
|
adapt_ethrdg_plrn¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. the adaptive diagonalization threshold for the effective polaron Hamiltonian is activated.
|
init_ethrdg_plrn¶
Type |
REAL
|
Default |
1.0d-2
|
Description |
Initial coarse threshold (in Ry) to be considered in the diagonalization of the effective polaron Hamiltonian.
|
nethrdg_plrn¶
Type |
INTEGER
|
Default |
11
|
Description |
Number of adaptive diagonalization thresholds to be considered, in logarithmic steps, until reaching final ethrdg_plrn.
|
io_lvl_plrn¶
Type |
INTEGER
|
Default |
0
|
Description |
I/O level of polaron calculations. If io_lvl_plrn=1, write/read electron-phonon matrix elements to file. If io_lvl_plrn=0, keep them in memory.
|
restart_plrn¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. self-consistent solution of polaron equations is skipped and post-processing calculations are activated.
|
interp_Bqu_plrn¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. \(B_{\mathbf{q}\nu}\) is interpolated into the fine q-grid or path.
|
interp_Ank_plrn¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. \(A_{n\mathbf{k}}\) is interpolated into the fine k-grid or path.
|
cal_psir_plrn¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. the real-space polaron wavefunction \(\Psi(\mathbf{r})\) is calculated (see step_wf_grid_plrn). Output file is written in .xsf format (psir_plrn.xsf).
|
step_wf_grid_plrn¶
Type |
INTEGER
|
Default |
1
|
Description |
Write \(\Psi(\mathbf{r})\) only in every step_wf_grid_plrn grid point of the original grid, given by the Wannier function .cube files.
|
scell_mat_plrn¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. the non-diagonal supercell calculation is activated for polarons.
|
scell_mat¶
Type |
INTEGER, DIMENSION(3, 3)
|
Default |
(/ (/1, 0, 0/), (/0, 1, 0/), (/0, 0, 1/) /)
|
Description |
Transformation matrix \(S\) from the unit cell to the (in general non-diagonal) supercell. \(\vec{a}_{s} = S \vec{a}_p\), where \(\vec{a}_{s}\) and \(\vec{a}_{p}\) indicate supercell and the unit cell lattice vectors, respectively.
|
do_tdbe¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. start time propagating the Boltzmann Transport Equation (TDBE).
|
dt_tdbe¶
Type |
REAL(KIND = DP)
|
Description |
Time step for TDBE propagation in femtoseconds.
|
nt_tdbe¶
Type |
INTEGER
|
Description |
Number of time steps for TDBE. Should be defined in
epwcom. |
twrite_tdbe¶
Type |
INTEGER
|
Description |
Interval for writing output during TDBE propagation.
|
temp_el_tdbe¶
Type |
REAL(KIND = DP)
|
Description |
Initial electronic temperature for TDBE simulations.
|
temp_ph_tdbe¶
Type |
REAL(KIND = DP)
|
Description |
Initial phononic temperature for TDBE simulations.
|
init_type_tdbe¶
Type |
CHARACTER(LEN = 75)
|
Description |
Type of initial carrier distribution.
|
init_sigma_tdbe¶
Type |
REAL(KIND = DP)
|
Description |
Gaussian smearing parameter for initial carrier distribution.
|
solver_tdbe¶
Type |
CHARACTER(LEN = 75)
|
Description |
Time propagation method for solving TDBE.
|
ef_c_tdbe¶
Type |
REAL(KIND = DP)
|
Description |
Initial energy of hot electron or chemical potential of electrons.
|
ef_v_tdbe¶
Type |
REAL(KIND = DP)
|
Description |
Initial energy of hot hole or chemical potential of holes.
|
carr_dyn_tdbe¶
Type |
INTEGER
|
Description |
Type of carrier dynamics in TDBE simulations.
1 = electron dynamics
2 = hole dynamics
3 = both electron and hole dynamics
|
dg_tdbe¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. use two different grids for energy and e-ph matrix elements.
|
nqf1d, nqf2d, nqf3d¶
Type |
INTEGER
|
Description |
Double grid dimensions for phonon q-points in TDBE simulations.
|
nkf1d, nkf2d, nkf3d¶
Type |
INTEGER
|
Description |
Double grid dimensions for electron k-points in TDBE simulations.
|
dph_tdbe¶
Type |
INTEGER
|
Description |
Ratio between time step for e-ph interaction and that for ph-ph interaction.
|
restart_tdbe¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. restart TDBE from a previous interrupted calculation.
|
phph_tdbe¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. include phonon-phonon scattering in TDBE simulations.
|
phwmin_tdbe¶
Type |
REAL(KIND = DP)
|
Description |
Minimum phonon frequency for phonon-phonon calculations.
|
ephmat_dir¶
Type |
CHARACTER(LEN = 100)
|
Default |
‘./’
|
Description |
Path to the electron-phonon matrix elements (
prefix.ephmat). |
lscreen_tdbe¶
Type |
LOGICAL
|
Default |
.false.
|
Description |
If .true. apply screening to e-ph matrix elements in TDBE simulations.
|